Hi,
thanks for your post, and sorry for the trouble.
Yes, that’s no problem in TablePress. You could even import this table into TablePress by copy/pasting the HTML code that you have now into the “Manual Import” field on the “Import” screen in TablePress.
Alternatively, you could manually create this on the “Edit” screen. Merging/combining cells is possible with the “colspan” and “rowspan” buttons below the table input fields there.
After that, you would just have to add a bit of “Custom CSS” code to achieve the same styling, if desired (e.g. following some examples from https://tablepress.org/faq/ ).
Regards,
Tobias